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Discovery of two rotational modulation periods from a young hierarchical triple system

中国科学:物理学、力学、天文学英文版 2023年第9期66卷 179-189页

作者： Yu-Tao Chen Hai-Jun Tian Min Fang xiao-xiong zuo Sarah ABird Di Liu Xin-Yu Zhu Peng Zhang Gao-Chao Liu Sheng Cui Center for Astronomy and Space Sciences China Three Gorges UniversityYichang 443002China School of Science HangZhou Dianzi UniversityHangZhou 310018China Space Information Research Institute Hangzhou Dianzi UniversityHangZhou 310018China School of Physics and Astronomy China West Normal UniversityNanChong 637002China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

GW Ori is a young hierarchical triple system located in λ Orionis, consisting of a binary(GW Ori A and B), a tertiary star(GW Ori C) and a rare circumtriple disk. Due to the limited data with poor accuracy, several short-period signals were detected in this system, but the values from diferent studies are not fully consistent. As one of the most successful transiting surveys, the transiting exoplanet survey satellite(TESS) provides an unprecedented opportunity to make a comprehensive periodic analysis of GW Ori. In this work we discover two significant modulation signals by analyzing the light curves of GW Ori's four observations from TESS, i.e.,(3.02 ± 0.15) and(1.92 ± 0.06) d, which are very likely to be the rotational periods caused by starspot modulation on the primary and secondary components, respectively. We calculate the inclinations of GW Ori A and B according to the two rotational periods. The results suggest that the rotational plane of GW Ori A and B and the orbital plane of the binary are almost coplanar. We also discuss the aperiodic features in the light curves;these may be related to unstable accretion. The light curves of GW Ori also include a third(possible) modulation signal with a period of(2.51±0.09) d, but the third is neither quite stable nor statistically significant.

关键词： GW Ori pre-main sequence fundamental parameters triple stars

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Effect of stress-relief annealing on thermal fatigue cracks for die-casting die steels

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Journal of Iron and Steel Research International 2024年第5期31卷 1164-1176页

作者： Zhi-xiong Bai xiao-chun Wu School of Materials Science and Engineering Shanghai UniversityShanghai200444China

The effect of stress-relief annealing at different stages of thermal fatigue tests on crack growth was investigated using a self-built thermal cycle *** results showed that annealing could limit crack expansion *** reduced dislocation density and released the accumulation of residual *** addition,the strain accumulation in carbides was reduced by this *** was also found that double annealing was even more effective at inhibiting crack expansion compared to single stress-relief *** 1000 cycles,the maximum crack length was reduced by 31.1%and 45.2%for the samples after using the optimal single and double annealing processes,*** single stress-relief annealing,earlier annealing provides more benefit in delaying crack ***,effective double stress-relief annealing requires a suitable time interval between the annealing ***,after 800 cycles,surface hardness decreased significantly accompanied by an increase in the size and number of carbides,and cracks expanded predominantly along grain boundaries.

关键词： Thermal fatigue Steel Carbide Stress-relief annealing Dislocation Residual stress

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Microbiome in Female Reproductive Health:Implications for Fertility and Assisted Reproductive Technologies

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 5-18页

作者： Liwen xiao Zhenqiang zuo Fangqing Zhao CAS Key Laboratory of Systems Biology Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Beijing Institutes of Life Science/Institute of Zoology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The microbiome plays a critical role in the process of conception and the outcomes of *** in microbiome homeostasis in women of reproductive age can lead to various pregnancy complications,which significantly impact maternal and fetal *** studies have associated the microbiome in the female reproductive tract(FRT)with assisted reproductive technology(ART)outcomes,and restoring microbiome balance has been shown to improve fertility in infertile *** review provides an overview of the role of the microbiome in female reproductive health,including its implications for pregnancy outcomes and ***,recent advances in the use of microbial biomarkers as indicators of pregnancy disorders are summarized.A comprehensive understanding of the characteristics of the microbiome before and during pregnancy and its impact on reproductive health will greatly promote maternal and fetal *** knowledge can also contribute to the development of ARTs and microbiome-based interventions.

关键词： Microbiome Pregnancy Female reproductive health Assisted reproductive technology Microbial biomarker

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Kinetic Resolution of Racemic 4-Substituted Chroman-2-ones Through Asymmetric Lactone Hydrogenation

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CCS Chemistry 2024年第10期6卷 2560-2576页

作者： xiong Wu Hai-Tao Yue xiao-Dong zuo xiao-Hui Yang Pu-Cha Yan Jian-Hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryFrontiers Science Center for New Organic MatterNankai UniversityTianjin 300071 Zhejiang Jiuzhou Pharmaceutical Co. Ltd.TaizhouZhejiang 318000

Esters are abundant in natural and synthetic products and their conversion into primary alcohols holds great importance in fine chemical ***,achieving asymmetric hydrogenation(AH)of racemic esters with remote stereocenters via kinetic resolution(KR)remains a formidable challenge due to the difficulties associated with discerning spatially distant *** address this issue,we have designed a hydroxy-assisted strategy that introduces a hydroxy group into racemicβ-aryl esters to facilitate hydrogenation and enhance chiral discrimination through a lactone *** employing chiral Ir-SpiroPAP catalysts,we achieved exceptional AH of racemic 4-substituted chroman-2-ones,lactone form of ortho-hydroxylatedβ-aryl esters,via KR,resulting in impressive selectivity factor(s)values of up to *** approach exhibited significant efficacy for racemic chroman-2-ones containingβ-aryl,alkenyl,alkynyl,and alkyl groups,enabling the synthesis of chiralγ-aryl primary alcohols and the recovery of chiralβ-aryl esters or chroman-2-ones,typically difficult to access using existing *** scalability and broad synthetic applications of this method were exemplified by successfully synthesizing chiral drugs(R)-fesoterodine and enrasentan,alongside various chiral intermediates essential for producing chiral drugs and natural *** promising results highlight the potential of this approach as a powerful tool for synthesizing valuable chiral compounds.

关键词： asymmetric hydrogenation chiralγ-aryl primary alcohols hydrogenation of esters iridium catalysts kinetic resolution

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Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong Zeng Chun-guang zuo xiao-yu Zhang Wei Li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

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Switchable Multicomponent Cyclization Reactions to Access Fluoroalkylated Dihydropyrimidines and Pyrimidines under Solvent-Free Conditions

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Chinese Journal of Chemistry 2024年第12期42卷 1394-1398页

作者： Wanqing zuo Zhizhen Zhu Yu Cheng Lingling zuo xiao Geng Zhifang Li Lei Wang College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistryof EducationHangzhouNormal UniversityHangzhouZhejiang311121China Advanced Research Institute and School of Pharmaceutical Sciences Taizhou UniversityJiaojiangZhejiang 318000China state Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Comprehensive Summary The development of switchable solvent-free multicomponent reactions to build high-value-added products is an important demand for organic ***,we detailed the successful implementation of a switchable strategy for the construction of diverse 4-fluoroalkyl-1,4-dihydropyrimidines and 4-fluoroalkyl-pyrimidines via a solvent/additive-free[3+2+1]annulation,starting from readily available enamines,trifluoroacetaldehyde hydrate or 1-ethoxy-2,2-difluoroethanol and amidines *** reaction conforms to the concept of green synthesis,and provides a new avenue to access valuable fluorinated heterocycles.

关键词： Fluorine chemistry Multicomponent reactions Environmental chemistry Heterocycles Enaminones Amidines

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Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： Bo-Wen Li Miao xiong Mei-Hua Liu Zhi-Gao Li Long Sang Zi-Han xiong Biao xiao Jian Pei xiao-Bo Wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

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Explainable artificial intelligence models for mineral prospectivity mapping

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Science China Earth Sciences 2024年第9期67卷 2864-2875页

作者： Renguang zuo Qiuming CHENG Ying XU Fanfan YANG Yihui xiong Ziye WANG Oliver P.KREUZER State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519000China Corporate Geoscience Group(CGSG) PO Box 5128 Rockingham BeachWA 6969Australia Economic Geology Research Centre(EGRU) College of Science and EngineeringJames Cook UniversityTownsvilleQLD 4811Australia

Mineral prospectivity mapping(MPM)is designed to reduce the exploration search space by combining and analyzing geological prospecting big *** geological big data are too large and complex for humans to effectively handle and *** intelligence(AI)algorithms,which are powerful tools for mining nonlinear mineralization patterns in big data obtained from mineral exploration,have demonstrated excellent performance in ***,AI-driven MPM faces several challenges,including difficult interpretability,poor generalizability,and physical *** this study,based on previous studies,we devised a novel workflow that aims to constructing more transparent and explainable artificial intelligence(XAI)models for MPM by embedding domain knowledge throughout the AI-driven MPM,from input data to model design and model *** newly proposed approach provides strong geological and conceptual leads that guide the entire AI-driven MPM model training process,thereby improving model interpretability and ***,the development of XAI models for MPM is capable of embedding prior and expert knowledge throughout the modeling process,presenting a valuable and promising area for future research designed to improve MPM.

关键词： Artificial intelligence Mineral prospectivity mapping Geological prospecting big data Domain knowledge Interpretability

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Metabolomic Analysis in Saliva and Different Brain Regions of Older Mice with Postoperative Delirium Behaviors

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Biomedical and Environmental Sciences 2024年第2期37卷 133-145页

作者： LIU xiao CAO Ying LIN xiao Wan GAO Dan Yang MIAO Hui Hui LI Tian zuo Department of Anesthesiology Beijing Shijitan HospitalCapital Medical UniversityBeijing 100038China

Objective Postoperative delirium(POD)has become a critical challenge with severe consequences and increased incidences as the global population ***,the underlying mechanism is yet *** study aimed to explore the changes in metabolites in three specific brain regions and saliva of older mice with postoperative delirium behavior and to identify potential non-invasive *** Eighteen-month-old male C57/BL6 mice were randomly assigned to the anesthesia/surgery or control *** tests were conducted 24 h before surgery and 6,9,and 24 h after *** C3(C3)and S100 calcium-binding protein B protein(S100beta)levels were measured in the hippocampus,and a metabolomics analysis was performed on saliva,hippocampus,cortex,and amygdala *** In total,43,33,38,and 14 differential metabolites were detected in the saliva,hippocampus,cortex,and amygdala,respectively.“Pyruvate”“alpha-linolenic acid”and“2-oleoyl-1-palmitoy-snglycero-3-phosphocholine”are enriched in one common pathway and may be potential non-invasive biomarkers for *** changes were observed in the three brain regions,with the upregulation of 1-methylhistidine and downregulation of *** Dysfunctions in energy metabolism,oxidative stress,and neurotransmitter dysregulation are implicated in the development of *** identification of changes in the level of salivary metabolite biomarkers could aid in the development of noninvasive diagnostic methods for POD.

关键词： Metabolomic Postoperative delirium(POD) Mechanism Biological marker

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Wireless electrical stimulation generated by piezoelectric nanomaterial promotes the dental pulp regeneration via regulating mitochondrial Ca^(2+)/PKA signaling pathway

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Journal of Materials Science & Technology 2024年第1期168卷 24-34页

作者： Jianmao Zheng Jiyuan zuo Cairong xiao Qining Guo xiaobin Fu Chengyun Ning Peng Yu Guangdong Provincial Key Laboratory of Stomatology Hospital of StomatologySun Yat-Sen UniversityGuangzhou 510080China School of Materials Science and Engineering National Engineering Research Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhou 510641China

The induction of dental pulp stem cells(DPSCs)into odontogenic differentiation is a cutting-edge method of dental pulp regeneration ***,it remains a challenge to develop biomaterials and ther-apies that can induce odontogenic ***,we propose a wireless electrical stimulation strat-egy to induce DPSCs odontogenic differentiation via K_(0.5)Na_(0.5)NbO_(3)piezoelectric nanoparticles(KNN)and polarized KNN(PKNN),which can be endocytosed by *** vitro,several odontogenic differentiation indexes were also increased in DPSCs treated with KNN and PKNN,and the increase was more obvious in the PKNN *** wireless electrical field promoted mitochondrial calcium concentration via mitochondrial calcium unidirectional transporter(MCU),increased the production of adenosine triphos-phate(ATP),and induced odontogenic differentiation through the activation of the cAMP-PKA signaling *** vivo,dental pulp-like tissue was induced by electrical stimulation wirelessly with KNN and PKNN,which was more clinically friendly compared with the wired device,and the induction was more obvious in the PKNN group consistent with in vitro *** conclusion,this work demonstrates the potential of PKNN as an effective stimulus that can induce odontogenic differentiation of DPSCs and be applied to dental pulp regeneration treatment.

关键词： Piezoelectric nanoparticles Dental pulp stem cells Odontogenic differentiation

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